Question 201972
Let x=amount of 2% acid needed
Then 60-x=amount of 6% acid needed
Now we know that the total amount of pure acid before the mixture ((0.02x+0.06(60-x))has to equal the total amount of pure acid after the mixture (0.05*60).  So our equation to solve is:

0.02x+0.06(60-x)=0.05*60  simplify
0.02x+3.6-0.06x=3 subtract 3.6 from each side
-0.04x=-0.6 divide each side by -0.04
x=15 qts--------------------amt of 2% acid needed
60-x=60-15=45 qts--------------amt of 6% acid needed
CK
0.02*15+0.06*45=0.05*60
0.3+2.7=3
3=3

Hope this helps----ptaylor